Stencil duplicating machine



March 18, 1941. A. SAMUELS STENCIL DUPLICATING- MACHINE Fi led Feb. 1, 1959 2 Sheets-Sheet l March 18, 1941; A LS 2,235,778

STENCIL DUPLICATING MACHINE Filed Feb. 1, 1959 2 Sheets-Sheet 2 Patented Mar. 18, 1941 ES ATENT' OFFICE STENCIL DUPLICATING MACHINE Abe SamuelsChicago, 111., assignor to Speed-- Print Corporation, Chicago, 111., a. corporation of Illinois Application February 1, 1939, Serial No. 254,062

6 Claims. (01. 101-116) This invention relates to improvements in peripheral engagement, as for example by the stencil duplicating machines, and particularly spring l3 acting on the roller mounting lever to the stencil carryingdrum thereof. M, as set forth in my co-pending application One of the objects of this invention is to pro- Serial No. 254,061 filed February 1, 1939, or by 5 vide a protective shield for the head of the stencil other suitable means. 5 positioned adjacent the lead end of the drum The stencil mounting drum comprises the segment and which arcuately tapers thereto, heads l5, only one of which is shown, and is whereby the impression roller is gradually enprovided with the usual foraminated segment l6 gaged and the initial shock of its tensioning secured to the heads l5, terminating at its segmeans absorbed prior to its cooperative engagemented ends in the inturned flanges l1 and I8. 10 ment against the stencil carried by the drum, so Extending substantially cordwise across the inthat tearing strains on the stencil head are eliminer surfaces of the heads l5 between the flanges hated and the life of the stencil preserved. ill and I8 are the angle bars or trenched inserts r Another object relatesto the construction and it. These insert bars act as ink baffles, as a operation of the protector shield, whereby it may reinforcing member for both the heads l5 and the be simply and speedily opened for permitting segment l6, and additionally serve to form. an the ink pad and stencil to be'secured and the cndwise engagement for at least the slide rod 2i] means for retaining it in such opened position carrying one end of the ink pad 2|, by means of during these operations; the simple, rapid and apertures 22 formed adjacent to the flange [8. positive means for clamping it down into pro- Pivoted to the heads l5 at 23 by means of leg tective position; and the means for causing it to portions, are the laterally extending curved flat automatically close down and'lock into protecsprings 24, retaining, by means of their doubletive position by normal operation of the duplibacked portions, the angular transversely extendcating machine in the event that it is inading clamp bar 25. This clamp bar 25 is adapted vertantly left open. to be swung on its pivotally mounted springs into A further object relates to the simple, rapid pressure engagement with the face of flange I8 and positive means for securing the ink pad and to securely clamp the lower end of the stencil stencil in place on the drum. it, and to draw it and the pad 2! beneath it Other objects relate to the simplicity and rugsmoothly around the foramina'fled Surface gedness of construction, the minimum number Mounted against each of the heads l5 adjaof parts, the details and arrangements of their cent the lead end of segment I6 is a bracket 21, construction, and the economies thereof, which pivotally engaged adjacent one edge at one point will be apparent from a consideration of the thereof by means of the threaded pin 28 and at r following specification and drawings, wherein: another point by means of threaded p 9 8 Figure 1 is a fragmentary elevation of a stencil tending through a radial slot 3|]. Also fixedly duplicating machine embodying my improvemounted on these pins are the legs of the button e bar 3! extending between the brackets 21. After Figure 2 is a fragmentary perspective view the bracket has been suitably fixed in desired with parts broken away of the stencil carrying D S y means of its pivot and t arrange- UNITED 40 drum showing the protector clamp in closed 130- ment, to compensate for wear, sli ht inacsition. curacies of manufacturing assembly, or other Figure 3 is a view similar to Figure 2, showing desirable adjustment, the lock nuts 32 and 33 the protector clamp in opened position. are turned own to securely and fixedly hold the Figure 4 is a fragmentary section through the brackets and button bar. The button bar is stencil carrying drum illustrating the protector provided with the usual stencil head engaging 45 clamp in closed position, and structural details studs 44 on its upper surface, and on its under thereof. side is provided with lips 45, which may be struck Figure 5 is a view similar to Figure 4, with out therefrom, forming a means whereby the ink the protector clamp in opened position. pad rod 46 may be engaged. 50

Referring to the drawings, the stencil clupli- Pivotally mounted at 34 to an inwardly offcating machine comprises generally the frame set portion 35 of brackets 21 are the bracket like It! carrying the drum H suitably journaled in legs 36 carrying the protector clamp 3'! adjathe sides of its frame, and cooperating therewith cent to its rearward edge. This protector clamp is the impression roller 12 yieldably retained in Bl is formed with a segmental surface and ex- 55 tends arcuately from a point inwardly of the periphery of the heads I arcuately to tangentially meet the segment it at its head end, when in closed position, and extends over and covers the button bar 3!. The offset portion 35 of bracket 21 terminates in an arcuately edged portion 38 generated about the pivot 34, terminating at one side in the shoulder 39, the other side being spaced from the bracket 21 to provide the outwardly open slot 40. The leg 36 of clamp 31 is provided with the radial slot 4! in which is retained an end of the transversely extending locking rod 42. Fixedly secured to the under surface of clamp 37 adjacent its free end is the strip spring 43 which acts against the locking rod 62, and when the slots 40 and M are in registry the spring urges the rod 42 downwardly so as to hold the clamp 41] in locked position and to prevent free pivotal movement.

When it is desired to engage 0r disengage the stencil or ink pad at their respective points of engagement at the button bar 3|, the locking rod 42 is manually gripped intermediate its length and raised in slot 4! out of slot 48 and the clamp 3? turned about its pivot 34, the rod 42 riding on the radial edge 38 until it strikes the shoulder 39, whereat it is additionally prevented from overriding by means of the lip 41 struck from the clamp 31. The button bar is thus uncovered, and the operator may freely carry out his opera tions in connection therewith, since the clamp will be maintained in opened position by reason of frictional pressure of the bar 42 against arcuate edge 38 by means of spring 43. After the ink pad and stencil head have been engaged to the button bar and it is desired to close the clamp to protective position, it is only necessary to turn the clamp about its pivot. until its outer beveled edge 48 substantially tangentially meets the segment i6, whereat the slots 40 and ll register and permit the rod 42 to enter the slot for locking engagement. In the event that the operator should inadvertently permit the clamp 3'! to remain open and commence to rotate the drum in its normal counter-clockwise operative direction, the clamp will strike the roller 12 and automatically be pivoted to locked position.

It will thus be seen that by means of the protective clamp 3'! which arcuately tapers to the surface of the ink pad and stencil carrying drum surface or foraminated segment It, the impression roller l2 under its operative pressure is peripherally engaged by the surface of the clamp 31 before it is brought into peripheral cooperative pressure engagement with the stencil carrying surface of the drum. Thus the initial and abrupt shock of engagement of the impression roller is eliminated and distributed over the clamp, so that strain against the head of the stencil is eliminated to preserve its life, and at the same time shock to the machine in general is lessened to preserve and lengthen the life of its various structural parts.

Although I have shown and described certain features of my improvements for the purpose of illustration, it will be apparent. to one skilled in the art that various changes may be made in the details and form of construction without departing from the spirit of my invention, and therefore, I do not wish to be restricted specifically thereto except as so limited by the appended claims.

What I claim is:

1. The combination with a stencil duplicating machine comprising a drum having a foraminated cylindrical segment surface adapted to support a stencil and an impression roller coacting in yieldable peripheral engagement therewith, of a protector clamp plate pivotally mounted on brackets therefor between the heads of said drum and extending arcuately to and terminating adjacent the lead end of said drum surface and adapted to progressively engage and depress said roller prior to its engagement. with the drum surface and to bring it into smooth engagement therewith, and locking means carried by said plate engageable with means formed on said brackets.

2. The combination with a stencil duplicating machine comprising a drum having a foraminated cylindrical segment surface adapted to support a stencil and an impression roller coacting in yieldable peripheral engagement therewith, of a protector clamp plate pivotally mounted on brackets between the heads of said drum and comprising a cylindrical segment surface of lesser radius than said foraminated segment and extending to and terminating at the lead end thereof in substantially tangential relationship and adapted to bring said roller into smooth initial engagement therewith, locking means carried by said plate engageable with means formed on said brackets, and spring means for yieldably retaining said plate in locked and in outwardly pivoted relationship.

3. In a stencil duplicating machine comprising a drum having a foraminated cylindrical segment surface adapted to support a stencil and an impression roller coacting therewith in spring tensioned peripheral engagement, a protector clamp plate pivotally mounted between the heads of said drum and adapted to extend arcuately to the forward end of said segment and to initially gradually engage said roller and to cause progressive reaction against the springs thereof and to thereby bring said roller into smooth peripheral engagement with said drum, automatic lock means for holding said protector clamp in operative position when pivoted thereto, and release means for opening it outwardly of the periphery of said drum.

4. In a stencil duplicating machine comprising a drum having a foraminated cylindrical segment surface adapted to support a stencil and an impression roller coacting therewith in spring tensioned peripheral engagement, a protector clamp plate pivotally mounted between the heads of said drum and adapted to extend arcuately to the forward end of said segment and to initially gradually engage said roller and to cause progressive reaction against the springs thereof and to thereby bring said roller into smooth peripheral engagement with said drum, self-locking means for holding said protector clamp to operative position, manual lock release means, and frictional means for holding said clamp in inoperative outwardly pivoted position.

5. In a stencil duplicating machine comprising a drum having a foraminated cylindrical segment surface adapted to support a stencil and an impression roller coacting therewith in spring tensioned peripheral engagement, a protector clamp plate pivotally mounted between the heads of said drum and adapted to extend arcuately to the forward end of said segment and to initially gradually engage said roller and to cause progressive reaction against the springs thereof and to thereby bring said roller into smooth peripheral engagement with said drum, automatic means for causing said protector clamp to become looked upon being pivoted into operative position, manual lock release means, and frictional means for holding said clamp in inoperative outwardly pivoted position, the said clamp being adapted from said latter position to be pivoted and automatically locked into operative position by engagement with said roller during operative rota- 10 tion of said drum.

6. In a stencil duplicating machine, a drum 

